【摘要】 为研究冻融循环对北方寒冷地区混凝土结构产生的不利影响,利用大连理工大学海岸和近海工程国家重点实验室的大型混凝土静、动三轴试验系统,对快速冻融循环0、25、50、75次的普通混凝土进行了单轴压,多轴压的力学性能试验,其中双轴压的应力比为1∶0.25、1∶0.5、1∶0.75、1∶1,三轴压的应力比为0.1∶0.25∶1、0.1∶0.5∶1、0.1∶0.75∶1和0.1∶1∶1的常规三轴和真三轴,测得了冻融循环后混凝土的单轴和多轴抗压强度,根据试验结果,系统地分析了冻融循环对混凝土单轴压及多轴压强度的不同影响,总结了应力比和冻融循环次数对处于多轴应力状态下混凝土强度的影响规律。结论表明:冻融循环后混凝土的双轴压和三轴压强度高于单轴抗压强度,提高程度与应力比有关。这些结论可为北方寒冷地区的混凝土结构,如水坝、混凝土桥梁、路面的抗冻设计提供理论依据。更多还原

【Abstract】 For the sake of studying the effect of freeze-thaw cycling on concrete structures,uniaxial compression and multi-axle compression strength of normal concrete were tested using the large static-dynamic tri-axial test system for concrete in the State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology after 0,25,50 and 75 cycles of rapid freeze-thaw.Stress radios were taken into account that design double-compression stress radios were 1∶0.25、1∶0.5、1∶0.75、1∶1,design general and true tri-axle compression stress radios were 0.1 ∶0.25 ∶1、0.1 ∶0.5 ∶1、0.1 ∶0.75 ∶1 and 0.1 ∶1 ∶1.The different effect of freeze-thaw cycling on uniaxial compression and multi-axle compression strength were systematically analyzed based on experimental results,laws of freeze-thaw cycling and stress ratios effect on concrete multi-axle compression strength were summarized.The conclusion showed that double-compression and tri-axle compression strength higher than uniaxial compression,the level that improved relative to uniaxial compression has relation with stress radios.The study result provided structural assign and analysis foundation for frost resistance of structures in northern region such as dam,concrete bridge and road,etc.更多还原